编译错误 Flutter ArCore 插件“类型不匹配：推断类型是 Activity？但 Activity 是预期的”

Question

I prepared everything in my flutter project for ArCore according to https://developers.google.com/ar/develop/java/enable-arcore?hl=en

(changes in AndroidManifest, build.gradle, gradle.properties). When trying to run the app I get the following error:

e: C:\Flutter\flutter_windows_3.3.1-stable\flutter.pub-cache\hosted\pub.dartlang.org\arcore_flutter_plugin-0.0.11\android\src\main\kotlin\com\difrancescogianmarco\arcore_flutter_plugin\ArcoreFlutterPlugin.kt: (32, 74): Type mismatch: inferred type is Activity? but Activity was expected

• What went wrong: Execution failed for task ':arcore_flutter_plugin:compileDebugKotlin'. Compilation error. See log for more details

I tried deleting "?" next to Activity in ArCoreView.kt line

 override fun onActivityCreated(activity: Activity?, savedInstanceState: Bundle?) {

but it didn't help. It looks like the problem is with the plugin. What other changes in its code should help? Is any of its version working correctly? Or what other thing to change to make it work?

Answer 1

You are using flutter version 3.3.1 which is null safe version and arcore_flutter_plugin version is 0.0.11, which is not null safe plugin. please use null safe version.

please use below version of arcore_flutter_plugin

arcore_flutter_plugin: ^0.1.0-null-safety.3

Answer 2

The only solution that worked for me was downgrading flutter to last non null-safety version (2.10.5)